1.The microdetermination of 11-dehydro-thromboxane B3 (11-dehydro-TXB3) in human urine is described. We prepared [^<18>O] 11-dehydro-thromboxane B3 for use as an internal standard (IS). Samples to which was added [^<18>O] analogue were extracted by chromatographic sample preparation using Sep Pak tC18 and silica gel column. Conversion of the extracted11-dehydro-thromboxane B3 to 1-methyl ester (ME) -11-n-propylamide (PA) -methoxime-9,11,15-tris-dimethylisopropylsilyl (DMIPS) ether derivative was followed by gas chromatography/high resolution-selected ion monitoring (GC/HR-SIM). Interfering substances from the urine matrix were eliminated during GC/HR-SIM analysis using a MP-65HT column. Good linear response over the range of 10 pg-100 ng/tube was demonstrated. We were able to detect 11-dehydro-TXB3 in the range from 26 to 375 pg/ml of the human urine. The present method can be applied to the determination of 11-dehydro-TXB3 in the human urine2.The microanalysis of 2,3-dinor-6-keto-pros
… Moretaglandin F1alpha (I) in human urine was developped. Samples to which was added [^2H4] -analogue as an internal standard were extracted by chromatographic sample preparation using Bond Elut C18, and silica gel. Conversion of the extracted I to 1-methyl ester-6-methoxime-9,11,15-tris-dimethy-lisopropylsilyl ether derivative was followed by gas chromatography/high resolution-selected ion monitoring (GC/HR-SIM). Inrerfering substances from the urine matrix were eliminated during GC/HR-SIM analysis.A method of the microdetermination of 2,3-dinor-DELTA^<17>-6-keto-PGF1alpha, a urinary metabolite of PGI3, is developped. An authentic 2,3-dinor-DELTA^<17>-6-keto-PGF1alpha was preparedfrom DELTA^<17>-6-keto-PGF1alpha incubated with homogenate of rat liver. [^<18>O] DELTA^<17>-6-keto-PGF1alpha was synthesized by repeating base-catalyzed hydrolysis of methyl ester derivatives in [^<18>O] water, to obtain an internal standard in gas chromatography/selected ion monitoring (GC/SIM) of DELTA^<17>-6-keto-PGF1alpha. Good linear response over the range of 10 pg-10ng was demonstrated. Chromatographic conditions using a MP-65HT column presented nearly baseline separation of DELTA^<17>-6-keto-PGF1alpha and 6-keto-PGF1alpha. We were able to detect DELTA^<17>-6-keto-PGF1alpha in the range from 6 to 26 pg/ml of the human plasma. The present method can be applied to the determination of DELTA^<17>-6-keto-PGF1alpha in the human urine and plasma. Less